No-Show-Engineered to stay hidden with sneakers, oxfords, athletic shoes and most casual styles. Visibility may occur with ultra-low collar shoes like boat shoes,etc . Four Size Available: S: US Women Size 5-8.5, Men Size 3-4 / M: US Women Size 9-12, Men Size 5-7 / L: US Women Size 12-14, Men Size 7-9/ XL-Extended Size: US Women Size 14-15, Men Size 10-12. Premium Material for Comfort：Crafted from a blend of soft and breathable fabrics, including cotton, spandex, and polyester. The cotton offers natural breathability, keeping your feet fresh throughout the day. Spandex provides just the right amount of stretch, ensuring a snug fit, while polyester adds sturdiness to withstand daily wear. Easy to wash: machine wash or hand wash, do not bleach Breathble: Made of breathable material, keeps your feet dry. Moisture management, Cushioned foot, Comfort toe seam. Occasions: Suitable for Running/Athletic/Casual shoes. Outdoor and Indoor.